[linux-dvb] tzap status output - what does it all mean?

[Rob <rob-linuxtv@noblesque.org.uk>]

Please excuse the dumb newbie question, but what do the numbers coming 
out of tzap mean and what should the values be?  (snr, ber, unc)

I have a Nova-T with the Conexant chipset.  After much messing about 
with CVS checkouts of dvb-kernel and video4linux, and a 2.6.10 kernel 
compiled from source (all on Debian unstable, BTW) I have a kernel and a 
set of modules that seem to work.  I can

tzap "BBC ONE" -r

and

cat /dev/dvb/adapter0/dvr0 > /store/tv.ts

and then sometimes if I rename the tv.ts to tv.mpeg, Window Media Player 
on another PC can play some TV.  (The PC with Linux and the nova-t in it 
is only a 400MHz PII, and has no monitor attached...)  Most of the time 
Media Player refuses to open the file though.

I've got the aerial right by the computer which is downstairs, which 
obviously isn't ideal (I can get some sort of signal by pointing it out 
of the window, which is about 90 degrees away from the transmitter, but 
does produce a picture when I have the nova-t in my Windows PC).  So I 
carried everything up into the loft and pointed the aerial in the 
general direction of the Sandy Heath transmitter.  From there, tzap 
reports something like this (from memory):

status ?? | signal 004f | snr ffff | ber 00000000 | unc 00000100 | 
FE_HAS_LOCK

(I can't remember what the status value was).

If I point the aerial 90 degrees away from the transmitter then snr 
drops a bit from ffff, ber becomes 00001400, and unc remains at 
00000100.  It looks to me like unc can't go above 0100?

I recorded the output from dvr0 to a file while the ber was equal to 
00000000, and Media Player refuses to play it (so does vlc).  The output 
from dvbsnoop seems to suggest that the the file is very corrupted 
(though there's a lot of output from dvbsnoop, and I'm new to this game...).

So to my original question, what does it mean if snr=ffff, ber=0 and unc 
is stuck at 0100?  I guess ber and unc ideally should both be zero?  
Should snr be a high value or low?  What's a good value for the signal 
reading?  An snr of ffff looks like the maximum value, which looks a bit 
bogus to me...?

--

Rob